@tetrameryx @CofCNatHistory State fossil of Illinois! #hometownhero

State Symbol: Illinois State Fossil  Tully Monster (Tullimonstrum gregarium ) The Tully Monster was a soft-bodied animal. It is preserved as outlines and flattened forms in nodules of ironstone from several areas in Illinois. It lived in the ocean that covered much of Illinois during the Pennsylvanian Period (about 300 million years ago). It was probably an active, swimming carnivore. The flexible body was probably round or oval in cross section. It may have been segmented, but some recent work suggests that it was not. The tail had horizontal fins and a dorsal fin; all three of the fins were triangular. The Tully Monster had a long proboscis. At the end was a jaw that contained eight small, sharp teeth. There is no evidence that the throat went down the proboscis. It seems more likely that the proboscis was a muscular organ used to pass food to the mouth. Near the midd...